Printing and other cylinders



Sept 179 1935. l.. T. A. ROBINSON PRINTlNG AND OTHER CYLINDERS Filed Nov. 28, 1935 2 Sheets-Sheet l ll@ W MM Y Patented Sept. 17, 1935 ir E aar orifice i PRINTNG AND OTHER CYLINDERS Leslie Thomas Albert Robinson, Sydenham, England Application November 28, 1933, Serial No. 700,128 In Great Britain February 29, 1932 6 Claims.

This invention relates to cylinders and more particularly to printing cylinders intended for use in rotary intaglio printing machines the cylinders being vof the kind described and claimed in my prior British specification No. 362,983 and which are made in at least two longitudinal segments and the present invention has for its object to provide 'a split printing cylinder of improved construction so as to facilitate tensioning of a forme or design sheet which is superimposed on and overlies the periphery of both segments of the cylinder.

According to the present invention a longitudinally split printing cylinder is provided wherein each segment is provided with separating faces disposed in different planes and enclosing an obtuse angle between them the apex of the obtuse angle on one'cylinder segment being adapted to co-cperate with a V shaped edge associated therewith. One segment is formed with an apical or V shaped recess engageable with an apical or V shaped edge extending longitudinally of and on an extended side of a four sided shaft lor on a co-operating segment so as to permit of relative rockable movement of the segments. The apical or V shaped edge aforesaid is formed by two contiguous sides of the shaft one of the said sides being bevelled or angled so that the angle between the said side and the contiguous co-operating side of the said shaft forms an acute angle. The shaft in one constructional form has thus two parallel sides connected by a third side which may be at right angles to the two parallel sides and a fourth side which is bevelled off or inclined so as to enclose an acute angle between the said bevelled side and the co-operating adjacent side of the shaft on which the segments are mounted. The angle between the jointing faces of each segment is an obtuse angle and the two segments carry one forme or design sheet. If desired the apical or V shaped edge may be provided on an integral part of one segment as hereinafter described. One end of the said forme or design sheet has rigidly secured to it a bar which is adapted to engage in a recess in one jointing or separating face of one cylinder segment the other end of the said forme or design sheet having a similar bar rigidly secured thereto and engaging a recess in the opposed jointing or separating face of the other segment. Two opposed joining or separating faces of the cylinder segments are thus each provided with a longitudinally extending recess to receive a bar asaforesaid. The engagement of the said barsl withthe respective recesses prevents outward displacement of the ends of the forme sheet when the latter is (Cl. lOl-415.1)

being tensioned during assembly of the two segments. To effect the rocking movement of the segment mounted on the apical or V shaped edge of the four sided shaft or segment a wedge or wedges or a cam or cams may be employed the said wedge or wedges or cam or cams being disposed between two jointing or separating faces of the cylinder segments.

In order that the invention may be clearly understood and readily carried into effect reference is made to the accompanying drawings which show diagrammatically and by way of example two constructional forms of printing cylinders in accordance with the present invention.

Figure 1 is a part axial section of a printing cylinder in accordance with the present invention.

`V.'Eigure 2 is an end view looking in the direction ofthe arrow A Figure 1.

Figure 3 is a cross section on the line 3--3 Figure 1 with the restraint and retaining rings removed. Y i l Y Figure 4 isa longitudinal section on the'line 4 4 Figure 3 showing the arrangement of the wedges and the part co-operating therewith.

Figure 5 is a cross section of a modified form of split printing cylinder showing the part provided with the apical or V shaped edge as being formed in one with the cylinder segment 2.

Referring to the drawings the segments are indicated by the reference numerals I, 2. As shown inthe drawings there are two conical wedges 3, l provided with internally screw threaded bores 5, 6. These two wedges 3, 4 are mounted on a spindle 'l common to b oth wedges and screwed externally as at 8, 9 to correspond'with the screw threaded bores in` the wedges 3, ll. It may be here remarked that the screw threads 8, 9 are of opposite hand. The spindle 'l is so shaped at each end that it can be rotated by a Spanner or other suitable means and the said spindle 'i is held against longitudinal displacement by collars l0, Il rigidly secured to the spindle Tand heldin position by cover or abutment plates I6, I 'l which are rigidly secured to the segment 2 of the cylinder. The conical wedges 3, i are movable in correspondingly shaped recesses I8, I9 part of each recess being provided in the segment l and the remaining portion of each recess being provided in the segment 2. YIt will be observed from the foregoing that the two'wedges 3, 4 are arranged lengthwise of and between opposed jointing or separating faces 2li, 2l of the cylinder segments l, 2 respectively. If so desired one continuous wedge of a suitable length may be employed the said wedge being actuated from either end of the cylinder. In the construction shown however the two wedges 3, 4 are displaceable simultaneously. The construction shown in the drawings and hereinafter described is intended for use with one forme or design sheet 22 the ends 23, 24 of which extend inwardly of and between the separating faces 25, 26 of the cylinder segments I, 2 respectively. The ends 23, 24 of the forme or design sheet are rigidly secured to bars 21, 28 disposed in recesses 29, 30 in the separating faces 25, 26 respectively. The two segments are supported on a shaft 3| having two parallel sides 32, 33 a third side 34 which may be at right angles to the two sides 32, 33 or of arcuate form and an inclined side 35 which forms an apical or V shaped edge 36 with the shaft side 33. It will be observed that the separating faces 25, 26 are of the same inclination as and are aligned with the bevelled or inclined face 35 of the shaft 3|. The contiguous sides 33, 35 of the shaft 3| form an acute angle which acts as the V shaped edge on the shaft 3|. The separating faces 20, 2| of the cylinder segments 2 extend through the V shaped edge 36 and these two faces are extended outwardly as at 31, 38 to the peripheral surface 39 of the cylinder segments and 2. The faces 31, 38 are of arcuate form the radii of curvature thereof lying in the V shaped edge 36 so as to permit of the rocking movement of the segment relatively to the segment 2. The gap between the ends 23, 24 of the forme sheet may be filled in by the use of suitable material such as described and claimed in the specicaton of my prior application for British Letters Patent No. 367,436.

In order to retain the cylinder segments in the assembled position the shaft 3| or one of the segments formed with stub ends 40, 4| each of which is provided with two externally screw threaded portions 42, 43, 44, 45 which are formed in one with the shaft 3|. In the constructional example shown the threads 42, 45 are right handed threads and the threads 43, 44 are left handed threads. The stub end 40 is provided with two diametrically opposite flat portions 46 which extend to the junction of the screw threads 42 and with the shaft 3|. The stub end 4| is provided with two flat portions 41 which extend to the junctions of the screw thread 43, 44 with the shaft 3|. Circular rings 48, 49 are provided to engage the screw threads 42, 45 and 43, 44 respectively the screw threads on the rings being internal screw threads and only extending through a suitable angle as for example 60 on diametrically opposite sides of the bores of the rings. Each ring 48, 49 is thus provided with diametrically opposed internal screw threads 50, 5| and 52, 53 which are of a segmental nature so that the rings can be turned through an angle of approximately 90 and then withdrawn from engagement with the corresponding screw threads on the shaft or from the stub ends formed on one segment. One cylinder segment is preferably rigidly secured to the shaft as shown more particularly in Figure 3 the other segment being mounted on the Shaft so that it can be allowed to rock a suitable distance to permit of the removal of the ends of a forme or design sheet from between the cylinder segments. The rings 48, 49 form clamping rings and abut against retaining rings 54, having partly cylindrical and partly conical bores 56, 51 which fit on to correspondingly shaped projecting ends 58, 59 on the ends of the cylinder segments 2. Each ring 48, 49 is provided with tommy holes to enable the rings to be rotated into the locking or unlocked position.

In Figure 5 the cylinder segment 2 is provided with a part 60 which is formed in one with the said segment. In this particular construction of printing cylinder the V shaped edge 36 is formed on the part 60 which is of integral form with the cylinder segment 2. In this construction the inclined side 35 is discontinued and is recessed to fit a triangular part 6| as shown in Figure 5. 62 is a bar extending the length of the segment and fitting tightly into its recess therein. The bar 62 acts to locate the segment when assembling the two segments and 2 and also acts to retain the segment in position when the segments are open to permit of the removal of the forme sheet ends. The screw threaded hole indicated in dotted lines in the bar 62 is intended for the insertion of a set screw in order to facilitate removal of the bar from the segment 2. The bar 62 is curved as at 63 the centre of curvature being located in the V shaped edge 36. Obviously the locating bar 62, may, if desired, be provided in the form shown in Figure 3 wherein, in its cooperation with the shaft 3| and the face 25, it serves exactly the same purpose as in the form shown in Figure 5. The conicity of the wedges 3, 4 may be reversed so that each converges outwardly instead of inwardly as shown in Figure 4.

What I claim is:-

1. A printing cylinder split longitudinally and comprising at least two segments, a shaft on which the segments are mounted and having two oppositely disposed parallel sides, a V shaped edge formed by two contiguous sides of the shaft, one of the said contiguous sides being a parallel side, the other contiguous side being at an acute angle to the extended adjacent parallel side of the shaft.

2. A printing cylinder split longitudinally and comprising two longitudinally disposed and superimposable segments, a four sided shaft on which the segments are mounted, the said shaft having two parallel sides connected by a third side inclined in such a direction as to form a V shaped edge on which one segment is adapted to be rocked, a resilient forme sheet having its ends extending inwardly of and between obliquely disposed separating faces of the cylinder segments.

3. A printing cylinder comprising a four sided shaft having two parallel sides connected by a third side at right angles to the two parallel sides, a fourth side on the said shaft inclined so as to enclose an acute angle between the said inclined side and an extension of one parallel side and forming a V shaped edge, a segment having obliquely disposed separating faces enclosing an obtuse angle between them and mounted on the V shaped edge formed on the four sided shaft, and a second segment co-operable with the first mentioned segment to tension maintain and retain a resilient forme sheet mounted on and overlying the peripheral surface of' the said segment.

4. A printing cylinder split longitudinally and comprising two segments, a forme sheet overlying the peripheral surface of the said segments, a bar rigidly secured to each end of the forme sheet and adapted to engage in a recess in one face of obliquely disposed separating faces on the said segment, the said bars being engageable in recesses in the obliquely disposed separating faces in the cylinder segment, a four sided shaft having an extended side and an adjacent side converbing thereto to form a V shaped edge on which one segment is rockably mounted after the manner of a see-saw.

5. A printing cylinder split longitudinally and comprising longitudinally disposed and superimposable segments, a forme sheet overlying the peripheral surfaces of the said segments each segment having obliquely arranged separating faces, a shaft having an offset V shaped edge co-operable with one segment to permit of rockable movement of the said segment, stub ends on the said shaft and segmentally screw threaded eX- ternally and provided with oppositely arranged flat sides, circular and internally segmentally screw threaded rings engageable with the segmentally screw threaded stub ends to retain the cylinder segments in assembled position.

6. A printing cylinder split longitudinally and comprising longitudinally disposed and superimposable segments, a forme sheet overlying the peripheral surfaces of the said segments, each segment having obliquely arranged separating faces, a V shaped edge integral with one segment and co-operable with the other segment to permit of relative rockable movement of the segments, stub ends having oppositely: arranged flat sides and segmentally screw threaded externally, and rings internally and segmentally screw threaded to engage with the segmentally screw threaded stub ends on the segments to retain the cylinder segments in assembled position.

LESLIE THOMAS ALBERT ROBINSON. 

